The article examines some theoretical issues related to the syntactic fixation of sentences in the Chinese language. The author gives the definition of a simple sentence and an adverbial modifier, as one of the minor but important members of the sentence, defining the place, time, reason, purpose, image and degree of action, etc. The article examines separately and in detail a place of an adverbial modifier in the structure of a simple sentence from the position of morphologic and syntax research. The author pays special attention to the difference in the localization of adverbial modifiers, depending on their typology, the presence or absence of negation, modal verbs, form words, to the inversion of an object occurring in a simple sentence. At the same time? only some of the most frequently seen adverbial modifiers are considered in this article. All theoretical calculations are provided with the examples illustrating the conclusion of the author.